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June 3, 1952 E. A. JONES PILOT AND MAIN BURNER UNIT Filed June 6, 1946 INVENTOR.

EDM/v ,4. Jam-=5 Patented June 3, 1952 County, Ohimassignor to-Ghrysler Corporation, Highland zPark; Mich, (i-corporation o;l1ela.=

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3;;Claims.

My present invention relates totheconst-ruction; of agas burner andpilot-device therefor.

It is a principal object of my invention-to provide a pilot flameconstruction-such'that the pilot flame orifices act'asanextension of the main fiamewhenthe main flameis ignited; the constructionbeing such that the pilot flame orifices draw-gas -irern --the --mai-n supply when the main supply is open,- and draw gas fron'ra mainvalve bleedline when the main supplyis shut -01f;

In-the drawings Fig. 1 disclosesin' schematic fashion apreferred embodiment of my invention, the parts being "illustrated in thepositions assumed for pilot flame operation; Fig. 2'- is a partial view showing a portion of the-burner with the -flameillustrated as it appears for a. short time after the main-flame isdgnited; Fig. 3 is aview similar to Fig. 2- showing the -main flame as it appears afterthepilot flame supply ceases; Fig. 4 is avertical section-through the pilot device-taken substantially along line 44 of Fig. 1; and Fig. 5-is-a partial plan view oi'th'e burner taken substantiallyalong line 5- --5 of Fig. 1.

Referring to-Figs. lto 5 inclusive there is illustrated a gas burner which is preferablyof the type claimed in my co-pending application No'.655,853-, filed March 20," 1946; and 'now: abandoned. The burner comprises-a -ho11ow -b'ody ll defining a chamber and having a longitudinal slot in its upper surface withinwhich is positioned a corrugated ribbon paokcomprising two corrugated-ribbons l2 separated by a spacerl3, thus -prov-idinga pluralityofclosely spaced ports of substantial length with respect to their greatest lateral-dimension. The gasis admitted to the interior-of the body I through an-inlet pipe l4 carrying a spudinot shown) through which there is a centrally drilled orifice-for creating a jet of gas. The gas jet enters a Venturi tube I5extending withinthe body H and providing means I or :inspirating primary air under control of anadjustableshutter l5.- Oneform of th'e device; asshown in Fig.- 1, utilizes: a tube liithat terminatesin about the mid portion:=of:"b0dy. l I. Qther types::of 'burners maybe substitutedafor the-type shown without departingofrom my invention; but-Ii prefer the. embodiment shownwfor reasons of simplicity and compactness" The as flow: n o. t e inlet pipe: -may be con rolled-in any-desir mann r a ashee illustrated ras controlled by a vvalve comprising anrinlet chamber 20. and-an dia n a utl t em.- heri-rzl. sepa atedya-substantia v or onta valve: 56313522? Posit oned above; the :valve seat thereais provided aqdiaphragm -23, the.centra1;por-

2 tion of which is-clamped between disks =24 and 25 by bolt 26;; The disks provide weighting-means in additiontoa valve surface adapted to engage the valve seat 22, so that if the pressure above the diaphragm substantially equals thepressure below-the-diaphragm the valve will be closed. In order to control the pressure above the diaphragm I provide an upper-chamber 30 of thesamecrosssectional area as the--combined-areasof chambers whenthe solenoid is deenergized- The solenoid is operated by a control device' such as a room thermostatr When-the valve 32is-open-the pressure in chamber 3!! equals the pressure'inthe inlet and outletchambers and the weight of the diaphragmcauses the supply valve-to close.-

Inorder that the diaphragm may bereopened l provide means for bleeding ofE-the gas from chamber 38 when the valve 32: closes. This means comprises a bleed opening -40-which oom- .municates'with-a pilot flame supply tube 4| :when

valveAZ isin raised position asillustrateda The tube :4 l isconnected to .the lowerexposedend'of a pilot tube -43 which preferably extends through the interionoi the. body as illustratedand claimed. in my aforesaid:co-pending application.

In said application the .pilot tube-is disclosed-as drawing primary. air from: outside-0f the burner body; bntinthepresent (embodiment oimy-present iinventi'onl prefen'to have the-burner tube 43rdraw-pr-imary-.airfrom within the burner body 1 l ;as,;by means.-ofiinspiratoraopenings 44. having aindrawna therethrongh bythe effect of a- .jet 45 inrthe tube. The, end of :tube. 43rabutsr 12118103161 surfacesiof theribbonmembers :l Ziand cl 3:50. that at least, one, usuallytwo .or three, of theports are in position to receive a. mixture. of gas-and primaryiairfromrthetube 43 when .gasis. .supplieck throueha the {tube 4 L; The. bypass; 3 l: x will beaonen toisupply as to the tube-.4 l; when'th'e main: as...supp y is. shIut-ofi. Under these condiitions air may enter the burner body through the remainder of the burner ports and through the Venturi tube l5 and primary air will thus be supplied to the openings 44.

In Fig. 1 I have illustrated a pilot flame safety device comprising a thermo-electric element 50 in position to be heated by the pilot flame, the operative element thereof being connected to a. solenoid device 5| which maintains the valve 42 in raised position as long as current is induced by the application of heat to the thermo-electric element 50. As long as either the pilot flame, indicated at 52, or the main flame, indicated at 53 (Fig. 3), is lighted the valve 42 will remain open. I have indicated at 54 a manual reset button for holding the valve 42 in raised position so that an initial supply of gas may be passed through the pilot device when the button is held down until heat has been applied to the device 50 long enough to generate current to maintain the valve in open position. There are many such control devices, available and I have illustrated onlysuflicient thereof to indicate the preferred arrangement.

In the operation of the device when the device is shut down the diaphragm 23 is seated on valve seat 22 by its own weight. If the pilot is out, as it would be after the initial installation the operator pushes on manual reset button 54 to open valve 42 so that an initial supply of gas may be supplied to the pilot. The operator then ignites the pilot and heat therefrom acts on thermo-electric element 50 to maintain valve 42 open. If the room thermostat 35 is satisfied and is not demanding heat then the solenoid 34 is energized and valve 32 and by-pass 3| are open. A supply of gas for the pilot may thus be obtained indefinitely from chamber 20, by-pass 3|, chamber 30, bleed opening 40 and tube 4|. When the room thermostat 35 calls for heat solenoid 34 is deenergized and valve 32 closed and pressure builds up in chamber while the pilot continues to withdraw gas from chamber 30. When the pressure differential between chambers 20 and becomes suflicient to lift diaphragm 23 the main valve is thus opened and gas is supplied through pipe [4 to burner H) to accommodate full burner operation.

As seen in Fig. 1 when the pilot flame is ignited and the thermostat 35 indicates that the room temperature is satisfied the diaphragm is seated on seat 22 and the main valve is closed. Gas may then escape from the chamber 30 through opening and tube 4| to the jet orifice to supply gas to the pilot flame 52. As soon as this escape of gas from chamber 30 effects a suflicient reduction in pressure in chamber 30 the diaphragm rises from its seat and the burner l0 commences operation. The pilot flame continues for an appreciable time after the main flame becomes ignited which produces a flame similar to that shown in Fig. 2. With one form of gas valve, specifically Minneapolis-Honeywell valve V-148A, which has the smallest upper chamber within my knowledge, this continued flow of pilot flame gas continues for approximately 15 seconds after the main valve is fully opened, thus creating a slight peak in the ribbon of flame as indicated at 55. After the pressure in chamber 30 becomes sufliciently reduced the pressure existing within the burner body II will cause mixed gas and primary air to enter the openings 44 and thus the ports above the tube 43 act identically the same as all other ports so that the main flame 53 is'the only flame existing.

However, the chamber 30 and the tube 4| remain filled with gas under pressure so that upon opening valve 32 a jet of pure gas will commence immediately to move through jet orifice 45. A flame will thus continuously burn from the ports above tube 43 even after the main flame goes out. Thus the pilot flame ignites the main flame, remains in evidence for an appreciable time interval after the main flame becomes established and then disappears so as not to disrupt the main flame, and is reignited from the main flame just before the main flame goes out. I have observed artificially created conditions simulating the action of the diaphragm valve in cocked position such that gas escapes over the valve seat 22 in insuiflcient quantities to maintain a continuous main flame. Under these conditions a continuous pilot flame exists and part or all of the main flame area may flash on and off. I have thus provided a burner and pilot device which fails safe.

In Fig. 1 I have indicated that the single main valve may be controlled by a plurality of simple control devices placed in parallel. Thus I have provided a tube 6!! drawing gas from the bypass 3| when valve 6! is open. The valve 6| may comprise a simple, spring-loaded valve having a rod 62 to open the valve against the compression of the spring. The rod may be moved by a bimetallic element 63 placed on the heat exchange chamber or flue therefrom and adapted to overcome the valve spring when an excessive temperature is created, thus providing a limit switch for the heating appliance. When the valve is open gas flows through tube 60 and a tube 65 leading to the upper chamber 30. Thus if either valve 32 or valve 5|, or both, are open the main valve will be closed and the pilot flame ignited. Other controls may be so positioned in parallel with each other so that as many control devices as are desired may be supplied. The valves will operate independently of each other and do not need complicated interconnecting tubing as required by all previous devices within my knowledge.

A further safety feature is illustrated in Fig. 1 in that a tube 56 connects tube 60 and the upper portion of the valve body against which valve 42 normally seats. If the pilot flame should become extinguished when the main flame is off the valve 42 will drop, thus opening communication between tube 66 and bleed opening 40 and assuring the establishment of pressure in chamber 3a regardless of the positions of valves 32 and BI. As long as this condition exists the diaphragm cannot be raised from its seat and the burner cannot be supplied with gas. Usually this will result in the closing of valves 32 and 5| since the room and the device heated by the burner will become cooled. Immediately upon depression of the manual button 54 the pilot device will be supplied with gas from the chamber 30 only, and should this prove insuflicient to reignite the pilot flame the same match or other lighting means being applied to the area of the pilot flame will ignite the main burner which is supplied with gas as soon as the diaphragm rises.

I claim:

1. A main and pilot gas burner assembly comprising-a hollow body defining a chamber and having a plurality of burner ports communicating with said chamber and extending through said body, said body having an orifice for the admission of primary air to said chamber, means for admitting a'main gas supply to sald'chamber for mixture with said primary air supply, a tubular pilot member extending through said body and into said chamber and having an outlet end located adjacent some of said ports, said tubular member having openings therethrough communicating with said chamber and having means including a jet orifice located within said member upstream of said openings adapted to deliver a high velocity fiow of gas past said openings to induce a mixture of air and gas from within said chamber to enter said pilot member through said openings to sustain a pilot flame at said end of said pilot member.

2. A main and pilot gas burner assembly comprising a hollow body defining a chamber and having a plurality of burner ports communicating with said chamber and extending through said body, said body having an orifice for the admission of primary air to said chamber, means for admitting a main gas supply to said chamber for mixture with said primary air supply, a tubular pilot member extending through said body and into said chamber and terminating in an outlet end in fluid flow registration with at least one of said ports, said tubular member having openings therethrough communicating with said chamber and having means including a jet orifice located within said member upstream of said openings adapted to deliver a high velocity fiow of gas past said openings to induce a mixture of air and gas from within said chamber to enter said pilot member through said openings to sustain a pilot flame at at least one of said ports.

3. A main and pilot gas burner assembly comprising a hollow body defining a chamber and having a plurality of burner ports communicating with said chamber and extending through said body, said body having an orifice for the admission of primary air to said chamber, means for admitting a main gas supply to said chamber for mixture with said primary air supply, a tubular pilot member extending through said body and into said. chamber and terminating in an outlet end in fluid flow registration with at least one of said ports, said tubular member having openings therethrough communicating with said chamber and having means including a jet orifice located within said member upstream of said openings adapted to deliver a high velocity flow of gas past said openings to induce amixture of air and gas from within said chamber to enter said pilot member through said openings to sustain a pilot flame at at least one of said ports, said tubular pilot member and the openings therein being operable to deliver mixed air and gas from said chamber to at least one of said ports when said main burner is operating and gas is not being discharged by said jet orifice.

EDWIN A. JONES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re. 22,760 Peterson .May 28, 1946 1,302,914 Goreau May 6, 1919 1,696,840 Dickinson Dec. 25, 1928 1,715,248 Reynolds et al. May 28, 1929 1,715,989 Calvert June 4, 1929 1,789,226 Ensign et a1. Jan. '13, 1931 1,820,510 Treck Aug. 25, 1931 1,949,030 Stocksmeyer Feb. 27, 1934 2,037,400 Tschiershwitz Apr. 14, 1936 2,263,170 Haedike Nov. 18, 1941 2,352,329 Koppel June 27, 1944 2,355,216 Guelson Aug. 8, 1944 2,474,547 Patch June 28, 1949 FOREIGN PATENTS Number Country Date 128,317 Switzerland Oct. 16, 1928 475,725 Germany May 8, 1929 

